Pressure equalizing package



Feb. 7, 1967 B. EDWARDS 3,302,822

PRESSURE EQUALIZING PACKAGE Filed on. 24, 1962 INVENTOR.

Brycmz? Edwards ATT'Y.

United States Patent 3,302,822 PRESSURE EQUALTZING PACKAGE BryantEdwards, Clarendon Hills, llll., assignor to lllinois Tool Works lino,Chicago, ill, a corporation of Dela- Ware Filed (let. 24, 1962, Ser. No.232,838

- 11 Claims. (Cl. 220-44) This invention relates in general to a packageconsisting of a container and a closure therefor, and more particularlyrelates to a container and closure member which sealingly engage eachother in a manner to provide a sanitary seal, but at the same timepermits the ingress of gas from the exterior to the interior of thecontainer when there is a negative pressure differential interiorly ofthe container relative to the exterior.

A packaging of foodstuffs in containers of the so-called vacuum varietyhas long been known. Quite conventionally these cans which are so-calledvacuum packed are made of metal with a tear strip or other means beingavailable to remove the outer enclosure to break the vacuum and provideaccess to the interior of the container for removal of the foodstuffs.Since the tear strip approach to vacuum packed foodstuffs led toundesirable sharp edges being exposed for contact with the human hand,different approaches to this problem have been tried. One such approachinvolves destruction of the outer cover. Since the contents of thevacuum packed containers are often only partially removed after initialopening of the vacuum container, a manually replaceable cover isdesired.

This invention is concerned with a one piece manually removable snap-ininner cover and its cooperation with an inner rim of a vacuum packedcontainer, which due to the configuration of either the inner rim and/orthe configuration of the cover, provides the functions of a sealingrelationship between the cover and the container, and also is easilymanually removable due to the pressure equalizing concept involved. Itwill be appreciated that normally a pressure differential exists betweenthe interior of the container and the exterior caused by the vacuumpacking operation. Thus after removal of the outer cover, it becomesgreatly desirable to provide a venting operation which will afford apressure equalization between the interior and the exterior of thecontainer. Otherwise atmospheric pressure will tend to make removal ofthe so-called manually removable inner lid extremely difficult. Aconstant venting inner lid, i.e., one which has a hole therethrough willserve this purpose but this has disabilities in that it does not providethe sanitary relationship desired relative to foodstuffs.

There are three essential qualities for any package utilized withfoodstuffs, namely, that the package be sanitary, the package materialmust be economical, and that the package must be designed such that itwill do its required job of containing within the parameters of itsexpected environment.

The general object of this invention is to provide a sanitary,economical, rugged package wherein there are two closure members; thefirst closure member cooperating with the container with sufficientstructural rigidity to withstand large pressure differentials betweenthe interior and the exterior of the container; the second or innerclosure member cooperating with the container in a. manner to normallyseal each other but which will, however, upon being exposed to apressure differential whereby the pressure is greater on the outside ofsaid second closure member relative to the interior of the container,will permit an equalization of the pressure without causing permanentdislocation of the inner closure member and permit same to reseal afterthe pressure is substan tially equalized.

Since vacuum packed containers having double closure 3,392,822 PatentedFeb. 7, 1967 members at the top thereof are generally vacuum packed fromthe bottom end of the container (the end opposite from the doublecovers), a pressure differential upon the drawing of the vacuum on theinterior of the container will occur between the first and secondclosure members. It is an object of this invention to provide a packageconstruction wherein the inner closure member cooperating with thecontainer may easily vent upon the drawing of the vacuum to permit thewithdrawal of air that is normally trapped between the inner and outerclosure members whereby a complete vacuum may be drawn on the foodstuffson the bottom end of the container, said inner closure member returningafter the venting thereof to a sealing relationship relative to thecontainer so as to prevent loose foodstuffs and the like interiorly ofthe container from shifting to the area intermediate the first andsecond covers during transportation, handling and storage of the unitsonce packed.

it is a further object of this invention to provide a novel closuremember to adapt to be an inner closure member for a vacuum packedcontainer, which is made with an integral knob means, is of one-piece,lightweight, economical plastic, is well adapted for mass productiontechniques, and may be formed from sheet stock material by a sheetforming molding method.

A still further object of this invention is to provide means on aclosure member of the type as above set forth which prevents saidclosure member, when it is free from the container and laid on a flattable surface, from sticking to such table surface upon attemptedremoval thereof by the housewife.

The novel features that are characteristic of the invention are setforth with particularity in the appended claims. The invention, however,both as to its organization and its method of operation, together withadditional objects and advantages thereof will best be understood by thefollowing description of specific embodiments when read in connectionwith the accompanying drawings, in which:

b FIG. 1 is a top plan view of one form of closure mem- FIG. 2 is asectional view of the closure member in FIG. 1 taken along lines 2--2 ofFIG. 1;

FIG. 3 is a sectional view through a vacuum pack container showinganother embodiment of lid similar to the one shown in FIG. 1 inassembled relationship to the container;

FIG. 4 is an enlarged fragmentary sectional view of one portion of theassembly shown in FIG. 3;

FIG. 5 is a view similar to FIG. 4 showing the venting action affordingingress of gaseous material interiorly of the container when there is anegative pressure differential interiorly of the container relative tothe exterior of the inner lid during the drawing of a vacuum from thebottom of a container;

FIG. 6 is a view similar to FIG. 5 showing the pressure equalizationtaking'place after the puncture of the outer lid whereby removal of theinner lid after complete removal of the outer lid is facilitated; and

FIG. 7 is a view of an alternate embodiment of lid and containerstructure affording substantially similar function of the lids andcontainers shown in the foregoing figures.

A package 10 shown in FIG. 3 :is of the vacuum pack variety andcomprises an inner lid 12, an outer lid 14, a bottom wall 16 andinterconnecting side walls 18, there being a collar portion means 19upon which the inner lid 12 is seated. Portions 14 through 19 arepreferably made of metal or some other material having sufficientrigidity to withstand the vacuum packing operation.

The collar means 19 comprises an upwardly slanting Q) circumferentiallycontinuous member 2% that projects radially inwardly of the container,there being a short vertically extending portion 22 which terminates atits upper end in a reversely rolled portion 24. The portions 20-22-24form an inner rim or lip portion which is both radially inward andaxially inward of the rim 28 of the top or outer lid 14 of thecontainer. The collar means 19 is attached to the side walls 18 by avertically extending portion 26 which is coextensive with a shortportion of the side walls 18 and is sealed to the side walls 18 and toprim 28 by a conventional beading process.

The lid or closure member 112, which adapted to be seated on the innerrim means 19, is preferably made from sheet form plastic material and inaccordance with the techniques set forth in my copending application,Serial No. 109,225 filed May 10, 1961. The lid 12 has a diaphragmportion 30 of substantial extent and centrally located integral knobmeans 32 which is configured so that it is easily manually graspable.The configuration of the knob means and how to obtain same is set forthwith more particularity in my aforementioned copending application. Thediaphragm portion 30 may be configured in any of a number of waysdepending upon the type of container within which it is to be used. Inthe instant case, the diaphragm portion is configured so that the lowestportion of the lid is immediately adjacent the knob means and the topportions of the knob means is on a level slightly below the outerperiphery of the rim means 34 of the lid.

The rim means or lip portion 34 surrounding the diaphragm portion of thelid is formed with a radially outward portion 36 and an upwardly reversetapered portion 38 which normally provides sealing engagement withportion 20 of the collar adjacent to portion 22. Immediately aboveportion 38 is a vertically extending portion 39 which has a lesser axialextent than portion 22 of the collar means 19 and which is normallyspaced from portion 22 a short distance in the radial direction. Ofparticular note is that portion of the side walls of the lid 12immediately above the straight portion 3%, namely, portions 40 and 42which provide a venting means. Portion 40 acts as an extension of and isgenerally disposed in the same plane as portion 39 although this is notcritical as long as it is spaced from the collar means 19. Rim

portion 42 is in the form of a plurality of upsets or emoutwardly fromportion 40- and terminates in a reversely extending downturned skirtportion 46 which overlays and surrounds portion 24 of the inner rim.

The lid depicted in FIGS. 1, 2, 4, 5 and 6 is substantially similar tothe device depicted in FIG. 3 except for the configuration of thediaphragm portion 3% and the addition of some seal preventing tabs 48and similar parts will be given similar reference numerals with thesuffix a. As shown in FIG. 4, portion 38a normally engages portion 20 ofthe rim to provide a seal at that point. It will be further noted thatportions 3%, 40a, 44a and 46a are normally slightly spaced fromcomplementary portions of the inner rim 19 of the container. Portion42a, being the radially outward portion of the projections or upsets inthe lip of the lid, engages the upper portion of the inner rim 19 at acamming angle. Upon the introduction of a vacuum to the bottom of acontainer (as depicted in FIG. 3) a pressure differential will normallybe obtained in the chamber intermediate the outer lid 14 and the lid 12and the remainder of the container. This creation of the pressuredifferential causes the diaphragm portion 30 to move inwardly causingportion 42a to move slightly downwardly and with a cam-like actioncausing the sealing portion 38a to disengage with portion 20, thespacing between the remaining portions of the lid allowing the pressureto equalize as indicated by the arrows in FIG. 5.

Once the pressure equalizes, portion 42a will again slide on the rimportion 24 adjacent to portion 22 causing the lid to return to theposition shown in FIG. 4, i.e., a sealing relationship. When loosefoodstuffs, such as coffee or the like, are disposed on the interior ofthe container, the return to the sealing relationship after the drawingof the vacuum is most important since the loose foodstuffs are thenprevented from getting into the immediate area between the inner andouter lid during transportation and handling of the containers.

When the outer container cover 14 is subsequently punctured as at 50during removal by a can opener or the like, air rushes into the aperturecreating a positive pressure on the diaphragm portion 30a causing apressure equalization to again take place which permits easy removal ofthe lid 12 via the knob by a housewife after complete removal of lid 14.The pressure equalization after puncture of lid 14 is shown in FIG. 6.

The lid shown in FIGS. 1, 2, and 4 through 6, due to the differentconfigurations of the diaphragm portion, has the greatest downward axialextent thereof substantially near the periphery thereof, such that whenthe lid is set upon a smooth table surface or the like, a greatlikelihood of the lid adhering to the smooth surface occurs if specialpreventative means are not employed. This is particularly true of wetsurfaces. To prevent this unwanted adhering from happening,supplementary seal pre* venting means in the form of small projections48 are circumferentially spaced around the lid at the lowermost axialextent thereof to prevent a suction cup action.

The embodiment shown in FIG. 7 differs from the foregoing in certainrespects and is similar in many respects and similar parts will beidentified with the similar reference numerals with the addition of thesuffix b. More particularly, FIG. 7 is a view similar to FIG. 4 showinga container inner rim and cover configuration wherein portion 4%provides a cam surface on the lid which cooperates with the rim of thecontainer similarly to portion 42a but the projection portion or ventingmeans is formed by grooves 52 upset in the rim portions 24b and 22b.Thus, upon creation of a pressure differential between the interior ofthe container and the exterior, venting will occur with theconfiguration shown in FIG. 7. The operation of the package shown inFIG. 7 will be substantially similar to the package shown in theforegoing figures.

Although the specific embodiments have been shown and described, it iswith full awareness that many modifications thereof are possible. Theinvention, therefore, is not to be restricted except in so far as isnecessitated by the prior art and by the spirit of the appended claims.

What is claimed as the invention is:

1. A pressure equalizing sanitary package comprising container meanshaving an open end defined by a first circumferential rim and a secondcircumferential rim radially inwardly of said first rim, one piecesnap-on manually removable closure means adapted to be inserted withinand retained on said second circumferential rim of said container means,said container means having a portion thereof offset radially outwardlyrelative to the smallest diameter of said second circumferential rim,said offset portion being adjacent said second circumferential rim, saidclosure means having an end wall portion for closing off said secondcircumferential rim and side wall means extending upwardly from said endwall portion, knob means formed in said end wall portion adapted to begrasped by the human hand of manual removal of said closure means fromengagement with said second circumferential rim, the side wall means andthe second circumferential rim of said closure and container meansrespectively each being formed with a sealing means portion for normallyengaging each other to seal said container means when in assembledrelation, and one of said side wall means and said secondcircumferential rim being formed with an integral venting means portionspaced from said offset portion of said container means outwardly fromthe interior of said container means, said venting means portion beingarranged relative to said respective sealing means portions to causetemporary disengagement thereof when the interior of said container isat a lower pressure than the exterior of said container to equalize thepressure therebetween and facilitate removal of said closure means fromsaid second rim of said container means.

2. The package set forth in claim 1 wherein a second closure member issealingly attached to said first circumferential rim and said pack-ageis maintained at a negative pressure difierential relative to ambientpressure when said second closure means is assembled to said firstcircumferential rim.

3. The pack-age set forth in claim 1 wherein the venting means is in theform of projections formed in the side wall of said one piece snap-onmanually removable closure means.

4. The package set forth in claim 1 wherein said venting means is in theform of groove means formed in said second circumferential rim.

5. A one piece snap-on manually removable integrally formed flexibleclosure member adapted to be inserted and retained on a container meanshaving an internal circumferentially continuous radially outwardlyoffset portion adjacent an open end thereof, said ofiset portion beingradially outwardly of the smallest diameter of the container adjacentthe open end thereof, said closure member comprising a relatively largediaphragm portion having integral knob means therein for closing off theopen end of the container means, said closure member having first,second and third side wall portions extending upwardly from saiddiaphragm portion, said first portion being adjacent said diaphragmportion and said second portion and radially outwardly of said diaphragmportion and said second portion, said first portion normally providingsealing engagement with said offset portion of said container means uponassembly of the closure member thereto, said second portion having adiameter less than the diameter of said first portion and formedintermediate said first and third portions, said third portion havingfirst and second subportions, said first subportion being in the form ofradially outward upsets spaced around the peripheral extent of saidsecond subportion of said third portion of said container side Walls,said first and second subportions being adapted to provide pressureequalizing means and cam means affording relative movement of said firstportion of said side wall means relative to said container means uponthe existence of the negative pressure difierential between the interiorof said container means and the exterior thereof after assembly of theclosure member thereto.

6. The closure member set forth in claim 5 wherein said knob memberprojects in a first direction from said diaphragm portion and nib meansin the form of projection means are formed in that portion of saiddiaphragm portion of said closure means extending the greatest dimensionfrom said knob means in the opposite direction, said projection meanspreventing said closure member from sticking to the smooth surface.

7. The closure member set forth in claim 5 wherein said closure memberis formed with a skirt portion'reversely extending relative to saidfirst, second and third side wall portions to prevent foreign bodiesfrom settling upon and entering into the venting means portion formed bysaid first and second subportions of said third portion of said sidewall means closely adjacent to said skirt portion.

8. A package comprising one piece snap-on manually removable plasticclosure means adapted to be retained on a container means, saidcontainer means and said closure means having complementary rim portionseach of which is formed with a sealing means portion for normallyengaging each other when assembled to seal the interior of saidcontainer means, and one of the rim portions of said closure means andcontainer means being formed with an integral venting means portioncausing temporary disengagement of said respective sealing meansportions so as to allow movement of gaseous material therepast from theexterior to the interior of the container while the closure and thecontainer are assembled and when the interior of the container is at alesser pressure than the exterior of the container, said sealing meansportions and said venting means portion being in vertically spacedrelation when the closure means is disposed at the top of the containermeans, said sealing means portions being located below said ventingmeans.

9. A package comprising a one-piece snap-on manually removable closuremeans adapted to be retained on an open mouth container, said containerand said closure means having complementary lip portions adapted to bematingly associated with each other, a circumferentially continuoussealing means portion provided on the lip portion of each of saidcontainer and closure means for engaging each other to completely sealthe interior of said container, and one of the rim portions of saidcontainer and closure means being provided with means causing temporarydisengagement of said sealing means portions from each other for theentry of air between the lip portions of said container and closuremeans when the interior of said container is at a lower pressure thanthe exterior of said container.

10. The package set forth in claim 9 wherein the closure means has knobmeans located thereon to facilitate manual removal thereof.

11. A package comprising a one-piece snap-on manually removable plasticclosure member adapted to be retained by and overlying the open upperend of a container, said closure member and said container havingcomplementary rim portions adapted to be matingly associated with eachother, said closure member having a diaphragm portion radially inwardlyoffset from its rim portion, the rim portion of said closure memberhaving vertically spaced upper and lower wall portions, the lower wallportion being peripherally continuous and having a dimension-a1 extentsuch that it underlies at least a part of said container rim portion oflocking and sealing said closure member on said container, said upperwall portion being in close proximity to and engaging another part ofsaid container rim portion at a camming angle thereto, and one of saidclosure and container rim portions in the vicinity of the upper wallportion of said closure member being provided with means including anintegral venting means portion causing sliding movement of said upperwall portion and displacement of said lower wall portion relative tosaid container rim portion for the entry of air between said closuremember and container when the interior of said container is at a lowerpressure than the exterior of said container.

References Cited by the Examiner UNITED STATES PATENTS 2,104,540 1/ 1938 Hotfman 22060 2,242,966 5/ 1941 Burkardt.

2,424,801 7/ 1947 Crabbe.

2,773,622 12/ 1956 Augensen 220-68 2,982,436 5/ 196 1 Hitov 220602,991,903 7/ 1961 Weiss 220--29 3,061,139 10/ 1962 Edwards 220-44 3,083,861 4/ 1963 Amberg.

3,133,669 5/ 1964 Scholtz 22097 3,147,879 9/ 1964 Scholtz 220293,240,383 3/ 1966 Scholtz 22044 THERON E. CONDON, Primary Examiner.GEORGE O. RALSTON, WESLEY S. COLE, Examiners. G. E. LOWRANCE, E. J.DRUMMOND,

Assistant Examiners.

1. A PRESSURE EQUALIZING SANITARY PACKAGE COMPRISING CONTAINER MEANSHAVING AN OPEN END DEFINED BY A FIRST CIRCUMFERENTIAL RIM AND A SECONDCIRCUMFERENTIAL RIM RADIALLY INWARDLY OF SAID FIRST RIM, ONE PIECESNAP-ON MANUALLY REMOVABLE CLOSURE MEANS ADAPTED TO BE INSERTED WITHINAND RETAINED ON SAID SECOND CIRCUMFERENTIAL RIM OF SAID CONTAINER MEANS,SAID CONTAINER MEANS HAVING A PORTION THEREOF OFFSET RADIALLY OUTWARDLYRELATIVE TO THE SMALLEST DIAMETER OF SAID SECOND CIRCUMFERENTIAL RIM,SAID OFFSET PORTION BEING ADJACENT SAID SECOND CIRCUMFERENTIAL RIM, SAIDCLOSURE MEANS HAVING AN END WALL PORTION FOR CLOSING OFF SAID SECONDCIRCUMFERENTIAL RIM AND SIDE WALL MEANS EXTENDING UPWARDLY FROM SAID ENDWALL PORTION, KNOB MEANS FORMED IN SAID END WALL PORTION ADAPTED TO BEGRASPED BY THE HUMAN HAND OF MANUAL REMOVAL OF SAID CLOSURE MEANS FROMENGAGEMENT WITH SAID SECOND CIRCUMFERENTIAL RIM, THE SIDE WALL MEANS ANDTHE SECOND CIRCUMFERENTIAL RIM OF SAID CLOSURE AND CONTAINER MEANSRESPECTIVELY EACH BEING FORMED WITH A SEALING MEANS PORTION FOR NORMALLYENGAGING EACH OTHER TO SEAL SAID CONTAINER MEANS WHEN IN ASSEMBLEDRELATION, AND ONE OF SAID SIDE WALL MEANS AND SAID SECONDCIRCUMFERENTIAL RIM BEING FORMED WITH AN INTEGRAL VENTING MEANS PORTIONSPACED FROM SAID OFFSET PORTION OF SAID CONTAINER MEANS OUTWARDLY FROMTHE INTERIOR OF SAID CONTAINER MEANS, SAID VENTING MEANS PORTION BEINGARRANGED RELATIVE TO SAID RESPECTIVE SEALING MEANS PORTIONS TO CAUSETEMPORARY DISENGAGEMENT THEREOF WHEN THE INTERIOR OF SAID CONTAINER ISAT A LOWER PRESSURE THAN THE EXTERIOR OF SAID CONTAINER TO EQUALIZE THEPRESSURE THEREBETWEEN AND FACILITATE REMOVAL OF SAID CLOSURE MEANS FROMSAID SECOND RIM OF SAID CONTAINER MEANS.